Assembly machine and method

ABSTRACT

Machine and method for assembly of workpieces such as primary and secondary weights of a transmission governor. Leading edge of the top flange of the primary weight is used to compress the coil spring seated on the secondary weight. An insert slide wipes the secondary weight and spring off of a carrier to assemble the secondary weight inside of the primary weight and to load the spring internally between the weights.

I A} r m United States term [15] ,Mfi,l Roofe Fe, 22, 1972 [54] ASSEMBLYMACHINE AWE MEE'IH UD [56] Melerenees Cited Inventor: l- ROOf B, Flint,

[ Assignw General Motels Cori-WWW, Detroit, 2,508,347 5/1950 Marsh.29/434 Mich.

. Primary Examiner-Thomas H. Eager [22] Filed 1970 Att0meyW. E. Finken,A. M. Heiter and Charles R. White [2!] App]. No.: 62,279

[57] AESTMC'JI Machine and method for assembly of workpieces such aspri- [52 us. Cl "29/434, 29/173, 29/200, y and secondary weights of atransmission s Lead- 74/763 ing edge of the top flange of the primaryweight is used to [51] Int Cl 823p 119/00 323p 13/00 compress the coilspring seated on the secondary weight. An Fieid 173 74/763 insert slidewipes the secondary weight and spring off of a carrier to assemble thesecondary weight inside of the primary weight and to load the springinternally between the weights.

5 (Ilaims, 7 Drawing Figures Pmmmmm W2 SWME a l 8 SHEET 1 8F 2 mamATTORNEY ASSEMBLY MACHINE AND METHUD This invention relates to a machineand method for assembling component parts such as the primary andsecondary weights and a coil preload spring of a two-stage governor.

Many automatic transmission controls employ a two-stage governor totailor the governor pressure curve to improve transmission control. Thetwo-stage governor generally has primary and secondary weights with apreload coil spring disposed therebetween. The secondary weight isarranged inside of the primary weight so that it acts directly on thegovernor regulator valve and the primary weight acts through the springon the secondary weight. At a predetermined transmission output speedthe primary weight reaches a stop so that only the secondary weights andsprings act on the regulator valve to extend the useful speed range ofthe governor.

Before the present invention the assembly of two-stage transmissiongovernors was a tedious, time-consuming, manual operation. Usuallyspecial fixtures were employed to hold the governor parts as the weightswere manually fitted to their carrier and a cap was installed to securethe weights to the carrier. The preload spring was then manually loadedinto a spring-retaining fixture and the governor was moved into thefixture to effect the installation of the spring between the pri' maryand secondary weights.

US. application Ser. No. 811,439 to Henri J. Van Lent et al., filed Mar.29, i969, now U.S. Pat. No. 3,541,887, dis closes a typical two-stagegovernor with primary and secondary weights suitable for assembly by themachine and method of this invention.

This invention provides a new and improved machine and method forconnecting the primary and secondary weights with the coil preloadspring as a subassernbly so that these parts can be subsequently joinedas a unit to the carrier. With this invention a primary weight is movedby a mechanical transfer device from a loading station to the assemblystation, a coil spring is then loaded on the spring retainer seat on asecondary weight which is mounted on a double-acting slide. The slidepositions the secondary weight in a predetermined position for assemblyoperation adjacent to the transfer device so that the primary weight cancompress the coil spring as it moves beyond a predetermined point. Aninsert slide carried by the slider is moved axially to cause thesecondary weight to be cammed inside of the primary weight. The springis moved from engagement with the top flange of the primary weight andwill begin to relax and engage a seat on the inside of the top flange ofthe primary weight. As the secondary weight is further moved vertically,it recompresses the spring and the spring will effectively hold theprimary and secondary weights in an assembled position ready forsubsequent assembly with the carrier and valve subassembly.

These and other objects, features and advantages will become moreapparent from the following detailed description and drawings in which:

FIG. l is a side diagrammaticai view of the assembly machine of thisinvention.

FIGS. 2-7 are side views showing a portion of MG. 1 to illustrate theoperation of the machine and the preferred method of assembly of theprimary and secondary weights and the preload coil spring.

As shown in FIG. ll there is a rotatable four-station transfer wheeldriven by a motor through drive shaft 12. The transfer wheel has seats14, 16, i8 and each provided with a magnet such as magnet 24! for seat14 to hold metal workpieces such as the primary weights 26 of atwo-stage governor. There is a loading chute 23 having a suitableescapement device, such as that shown in U.S. Pat. No. 3,473,676, issuedOct. 2i, l969 to J. D. Cotney, for serially feeding the primary weights26 into the seats 14-20 as the seats are moved into a loading positionbeneath the chute. The chute 23 has a suitable opening 30 formed thereinto permit the transfer wheel to move the primary weights 26 from theloading station to an assembly station 32. The lever has an outer shroud34 which provides a cover for the transfer wheel and for the primaryweights as they are moved from the loading station to the as unit semblystation. A tubular discharge chute 35 is employed to feed the workpiecesafter assembly from the machine to a storage hopper or other device forsubsequent assembly.

The preferred embodiment has a suitable support or table 36 to whichchute 35 is attached and on which is mounted a longitudinally movableslide assembly 3%} for transferring second and third workpieces formedby secondary weight 410 and a coil spring #2 from a second loadingstation to the assembly station 32. The slide assembly comprises acarrier member 44 mounted for axial sliding movement in a suitablechannel or groove in the support 36. Slidably mounted on the carriermember 44 are an intermediate or injector slide as and a top plate iii.A strap 54 extends from carrier member 44 and loops over slide 416 andplate 48 to retain these slidable elements on the carrier member. Thetop plate carries a pin 50 which projects downwardly into an elongatedslot 52 formed in the intermediate slide as. The rearwardly extendingportions of the components of the slide assembly provide handle meansfor moving the slide assembly axially. The top plate 43 has a verticallyextending front portion 55 which is provided with a magnet 56 that holdsthe preload coil spring 412 in position on the top slide. The carriermember M has a forward upper surface that forms a seat 53 for thesecondary weight as the slide assembly is moved to transfer thesecondary weight and spring from the loading position illustrated inFIG. 1 to the assembly station 32.

The secondary weight M) has a spring-retaining boss 60 formed on theinside of one of its legs 152 on which coil spring 42 is seated when itis loaded on the secondary weight. The other leg 64 extends obliquelyfrom leg 62 and has a vertically extending portion that terminates in aninwardly curved tip 66 which provides the mechanical contact for thegovernor valve element. Leg 64 has ear members 68 each with an openingfor reception of a pin to movably secure the primary and secondaryweights to each other and to the carrier and cap. The primary weight hasspaced upper and lower flanges 7i) and 72 to receive the secondaryweight and allow pivotal movement of the secondary weight relative tothe primary weight. The top flange has a front edge 73 used to compressthe preload spring in the preferred way of practicing the method of thisinvention. Also the top flange 70 has an inner boss 74 to provide aretaining seat for spring 412 when installed. Tire primary weight hasspaced ears 76 each with an opening 78 to receive the pivot pin used toattach the weights to the carrier and cap.

In a preferred operation a primary weight 26 is fed from a hopper orother suitable supply through the loading chute 23 onto a seat on thetransfer wheel 10 as the secondary weight is fed onto the seat 58 of theslide member Ml in the loading position. At this time the coil spring412 is fed by a suitable loading device onto the boss 741 of thesecondary weight and it is held in this position by the magnet 56.Manually or by suitable motor means, not shown, the slide assembly 38 isthen moved axially as a unit to the left moving the secondary weight andspring. With this movement the coil spring 42 is positioned in alignmentwith the front edge '73 of the top flange of the primary weight as it ismoved close to the assembly station as shown in FIG. 2. The curved tip66 ofleg 6d of the secondary weight is positioned just inside of thefront edge of the bottom flange 72 of the primary flange so that thesecondary weight will enter into the space between. the flanges 70 and'72 as the transfer wheel llil continues turning to compress spring 412as best shown in FIG. 3.

FIG. Al shows the transfer wheel stopped at the assembly station. Thecoil spring 42 is compressed and moved from the magnet 56 by the primaryweight and leg as of the secondary weight has been further positionedbetween the top and bottom flanges of the primary weight.

After spring compression the injector slide as is moved by a suitablemotor axially relative to top plate lli and carrier member 44 to beginwiping the secondary weight off of seat 58 on the carrier 44L As shownin FIG. 5 leg as of the secondary weight is further inserted into theprimary weight and the spring 42, as it is pushed off of the edge 73,will relax and begin to seat on the inner boss 74 of the top flange '70of the primary weight. FIG. 6 illustrates the end of travel of theinjector slide 46 as limited by pin 50 and slot 52; the secondary weighthas been pushed completely into the primary weight and the coil springis compressed between the primary and secondary weights to hold theweights together to form a subassembly. As illustrated in FIG. 7 theslide assembly 38 is being retracted to pick up another secondary weightand spring. The transfer wheel 10 is then turned and the inner wall ofthe discharge chute wipes the subassembly of the weights and spring fromthe wheel 10 and this chute delivers the subassembiy to a container orconveyor for further operation such as connection to the carrier memberand cap. Transfer wheel 10 has at this time picked up another primaryweight in seat for additional assembly operation.

While a preferred method and embodiment of this invention has been shownand described, it will be appreciated that this invention is not limitedto the particular construction and method disclosed since others willnow be apparent to those skilled in the art. Therefore, this inventionis set forth in the following claims.

I claim:

1. In an assembly machine for assembling a spring and two workpieces ina unit comprising a transfer member for moving a first workpiece from aloading station to an assembly station, transfer means supporting asecond workpiece, retainer means for holding said spring on said secondworkpiece, means for moving said transfer means to said assembly stationso that said first workpiece can subsequently compress said spring onmovement of said first workpiece beyond a predetermined point, andinjector means to move said second workpiece and said spring relative tosaid transfer means to insert said second workpiece and said spring intosaid first workpiece and thereby compress said spring between saidworkpieces.

2. In an assembly machine for assembling a coil spring and primary andsecondary weights for a transmission governor comprising first andsecond loading stations, an assembly station, transfer means fortransferring a first of said weights from said first loading station tosaid assembly station, slide means for transferring a second of saidweights from said second loading station to said assembly station, saidslide means having retainer means for holding said coil spring in apredetermined position on said second weight, means for moving saidslide means to a position whereby said spring means is axially alignedwith a portion of said first weight so that said first weight cancompress said coil spring means, and injector means movably mounted onsaid slide means for pushing said last-mentioned weight and said springmeans within said firstmentioned weight whereby said weights are heldtogether in an assembled position by a force exerted by said spring onsaid weights.

3. The machine defined in claim 2 wherein said transfer means is arotatable wheel having a plurality of coplanar seats with holding meansfor holding said primary weights for serial movement of said primaryweights from said first loading to said assembly station, said slidemeans having a top plate with a front face portion and a baseplatehaving a seat for said secondary weight, and magnet means in said faceportion to retain said coil spring on said secondary weight as saidslide means moves said secondary weight and said coil spring to saidassembly station.

l. A method of assembling first and second workpieces with spring meanscomprising the steps of loading said first workpiece on a transferdevice, positioning said spring means on said second workpiece, movingsaid second workpiece and said spring means into a predeterminedposition for assembly with said first workpiece, transferring said firstworkpiece by said transfer device to said assembly position andsubsequently compressing said spring through an external part of saidfirst workpiece, shifting said second workpiece in an axial direction tomove said spring from engagement with said external part of said firstworkpiece and causing said second workpiece to turn inside of saidworkpiece so that said spring seats on an internal part of said firstworkpiece and subsequently is compressed between said workpieces toretain said workpieces in an assembled position.

5. A method of assembling primary and secondary weights with coil springmeans comprising the steps of loading said primary weight on a firsttransfer device,'loading said secondary weight on a second transferdevice, positioning said coil spring on said secondary weight, movingsaid second transfer device and said secondary weight and said springmeans into a predetermined position for assembly with said primaryweight, transferring said primary weight to said assembly position toinsert a portion of said secondary weight in said primary weight and tocompress said spring through an external part of said primary weight,shifting said secondary weight and said spring in an axial directionrelative to said second transfer device to cause said spring to movefrom engagement with said external part of said primary weight and relaxinto engagement with internal boss on said primary weight, and movingsaid secondary weight further within said primary weight so that saidspring is recompressed to exert a spring force to retain said weightsand said spring in an assembled position.

1. In an assembly machine for assembling a spring and two workpieces in a unit comprising a transfer member for moving a first workpiece from a loading station to an assembly station, transfer means supporting a second workpiece, retainer means for holding said spring on said second workpiece, means for moving said transfer means to said assembly station so that said first workpiece can subsequently compress said spring on movement of said first workpiece beyond a predetermined point, and injector means to move said second workpiece and said spring relative to said transfer means to insert said second workpiece and said spring into said first workpiece and thereby compress said spring between said workpieces.
 2. In an assembly machine for assembling a coil spring and primary and secondary weights for a transmission governor comprising first and second loading stations, an assembly station, transfer means for transferring a first of said weights from said first loading station to said assembly station, slide means for transferring a second of said weights from said second loading station to said assembly station, said slide means having retainer means for holding said coil spring in a predetermined position on said second weight, means for moving said slide means to a position whereby said spring meanS is axially aligned with a portion of said first weight so that said first weight can compress said coil spring means, and injector means movably mounted on said slide means for pushing said last-mentioned weight and said spring means within said first-mentioned weight whereby said weights are held together in an assembled position by a force exerted by said spring on said weights.
 3. The machine defined in claim 2 wherein said transfer means is a rotatable wheel having a plurality of coplanar seats with holding means for holding said primary weights for serial movement of said primary weights from said first loading to said assembly station, said slide means having a top plate with a front face portion and a baseplate having a seat for said secondary weight, and magnet means in said face portion to retain said coil spring on said secondary weight as said slide means moves said secondary weight and said coil spring to said assembly station.
 4. A method of assembling first and second workpieces with spring means comprising the steps of loading said first workpiece on a transfer device, positioning said spring means on said second workpiece, moving said second workpiece and said spring means into a predetermined position for assembly with said first workpiece, transferring said first workpiece by said transfer device to said assembly position and subsequently compressing said spring through an external part of said first workpiece, shifting said second workpiece in an axial direction to move said spring from engagement with said external part of said first workpiece and causing said second workpiece to turn inside of said workpiece so that said spring seats on an internal part of said first workpiece and subsequently is compressed between said workpieces to retain said workpieces in an assembled position.
 5. A method of assembling primary and secondary weights with coil spring means comprising the steps of loading said primary weight on a first transfer device, loading said secondary weight on a second transfer device, positioning said coil spring on said secondary weight, moving said second transfer device and said secondary weight and said spring means into a predetermined position for assembly with said primary weight, transferring said primary weight to said assembly position to insert a portion of said secondary weight in said primary weight and to compress said spring through an external part of said primary weight, shifting said secondary weight and said spring in an axial direction relative to said second transfer device to cause said spring to move from engagement with said external part of said primary weight and relax into engagement with internal boss on said primary weight, and moving said secondary weight further within said primary weight so that said spring is recompressed to exert a spring force to retain said weights and said spring in an assembled position. 